On a wall of the US ambassador's residence in Pretoria hangs a unique photograph: the shadowy silhouette of Barack Obama bending to shake the hand of a smiling, seated Nelson Mandela. Taken seven years ago in Washington, it documents the only meeting of America's and South Africa's first black presidents.

From dawn on Wednesday, the framed picture formed part of the backdrop to rolling election coverage at a champagne breakfast hosted by the US ambassador, Donald

Gips. Whatever the disappointments of Obama's first term, there was little doubt who the South Africans present were rooting for.

Lindiwe Zulu, international relations adviser to President Jacob Zuma, and openly pro-Obama, said: "We are hoping that this time around he will even be able to visit South Africa, because if he doesn't, we won't forgive him for that!" Obama has been criticised for spending less than 24 hours in sub-Saharan Africa during his first term – a flying visit to Ghana in 2009.

Zulu continued: "We also hope that in the next four years Africa will occupy a higher space in his agenda.

"In his own words, he says the best is yet to come, so we're looking out for that best that he's talking about from an African perspective."

Zuma offered his own congratulations. "We value our relations with the United States and look forward to strengthening bilateral co-operation in the years to come," he said.

The US remained important to Africa's development, Zuma added. "South Africa is confident that the United States will continue to play a positive role in this regard."

Obama's victory was immensely popular across the continent, nowhere more so than in Kogelo, the Kenyan village where his late father was born. Obama's stepgrandmother, Mama

Sarah, was quoted by the Daily Nation newspaper as saying: "Much as I must thank the American people for this gesture, victory is Africa's as it solidifies our position in world leadership."

The 90-year-old said there were many factors in Obama's triumph but stressed two of them: "It is God's plan and, most of all, he is an outstanding gentleman."

The chorus of congratulation was joined by the Nigerian president, Goodluck Jonathan, whose own election campaign borrowed conspicuously from Obama's.

A government statement said: "President Jonathan welcomes president Obama's victory in an intensely fought presidential race as an endorsement by the good people of the United States of his leadership, progressive world view and the very good work he has done in the past four years towards ending global economic depression and fostering global peace and security."

In Zimbabwe, which is facing its own election next year, the education minister, David Coltart, tweeted: "Congratulations @BarackObama on your victory. My prayer is that you will use your 2nd term to help the #peace process in #Zimbabwe."

He added: "It takes an election in such a vast country and so close to show us #Zimbabweans what we need to do if we are to respect our right to elect."